Are SSRIs Effective for Treating OCD?

Clinical Question

Evidence-Based Answer

SSRIs are effective for the treatment of OCD. If it is assumed that 10 percent of persons with OCD will recover without treatment, then 12 persons with OCD need to be treated for one additional person to have a response within six to 13 weeks. If it is assumed that 20 percent of persons with OCD will recover without treatment, then six persons would need to be treated.

Practice Pointers

In the United States, the prevalence of OCD is approximately 2 percent of the population. About one half of persons with OCD have episodic symptoms, and one half have a more chronic clinical course. Complete remission rates are 10 to 20 percent.

This review found 17 studies that included 3,097 adults with OCD. Studies were randomized controlled trials and quasi-randomized trials comparing placebo with f luoxetine (Prozac); f luvoxamine (Luvox; brand only available in the United States in extended-release capsules); sertraline (Zoloft);paroxetine(Paxil);citalopram(Celexa); or escitalopram (Lexapro). Response to treatment was defined as at least a 25 percent reduction in the Yale-Brown Obsessive Compulsive Scale score and improvement on a dichotomous global impression scale. SSRIs as a class and each SSRI studied individually were more effective than placebo. Nausea was the most commonly reported adverse effect.

A Cochrane review comparing cognitive behavior therapy (CBT) with the usual treatment for OCD found that CBT also significantly reduced symptoms.1 The American Psychiatric Association recommends CBT and SSRIs as first-line treatments. Patients who are appropriate candidates for a trial of CBT alone include those who do not have severe depression or anxiety and who can cooperate with treatment. Patients who might consider an SSRI alone are those who cannot or will not cooperate with CBT, who have done well on medication before, or who prefer medication alone. Combined treatment is appropriate for those who fail monotherapy, would like to discontinue SSRI treatment, or have other comorbid psychiatric conditions.2